1. Field of the Invention
The present invention is directed to a trimmer construction for electric shavers, and, more particularly, to a trimmer unit adapted in use to be incorporated in electric shavers with or without a main cutter.
2. Description of the Prior Art
A trimmer unit adapted to electric shavers with a main cutter is well known, for example, as disclosed in U.S. Pat. No. 3,552,007. In that patent, a trimmer unit is disposed adjacent the main cutter and operated directly from the drive source for the main cutter. As seen in this patent, the prior trimmer unit is basically composed of two members disposed in a stacking arrangement with one another. One is a trimmer base mounted on the housing of the shaver and carrying at the end stationary and movable cutters, and the other is a trimmer drive member mounted on the trimmer base for connection with the drive source of the main cutter and the movable cutter in such a way as to reciprocate the movable cutter upon receiving the driving force from the drive source. In view of that, certain thickness is required for each of the trimmer base and the trimmer drive member to impart sufficient mechanical strength thereto. The above stacking arrangement of the parts results in an increased thickness of the trimmer unit; this counteracts the demand for reducing the thickness of the trimmer unit or incorporating it in the shaver without adding extra or undue thickness thereto. In addition to the above, the trimmer drive member employed in the prior art shavers is normally in the form of a lever which is pivoted to the trimmer base by means of a pin with one end thereof connected to the movable cutter and with the other end thereof being in engagement with the drive source of the main cutter. As a result of this arrangement, the movable cutter is driven to reciprocate as the pivoted lever is operated by the driving source to pivot about the pin. Consequently, the prior art shavers have the drawback of suffering friction noises resulting from the mechanical linkage between the lever and the trimmer base, and particularly resulting from the pivotal movement of the driving element about the pin and/or associated sliding movement of the lever on the trimmer base. In connection with the above, the trimmer unit employed in prior art shavers requires a large number of parts including the above lever and linkage thereof which are assembled only with difficulty.